Preheat oven to 350℉.
In medium sized bowl, beat together the cream cheese and sugar until smooth.
250 g - 1 package cream cheese, room temp, 3 tablespoon - white granulated sugar
Add the egg yolk, vanilla and salt. Mix until combined. Set this aside.
1 - large egg yolk, pinch - salt, ¼ teaspoon - vanilla extract
Melt the butter and add cocoa powder while it's still warm.
½ cup - unsalted butter, melted, ¼ cup - cocoa powder
In another bowl, beat together the eggs and sugar with an electric mixture for 3-5 minutes, until the sugar is dissolved. Feel the mixture between two fingers, it shouldn’t be grainy.
2 - large eggs, ¾ cup + 2 tablespoon - white granulated sugar
Mix in the food colour and vanilla.
½ teaspoon - red gel food colouring, ½ teaspoon - vanilla extract
Add the butter and cocoa mixture to the eggs, and the vinegar and beat until combined.
1 teaspoon - vinegar
Add the flour, salt and gently mix with spatula. Make sure to not overmix - stop when there's no streaks of flour left. Set this aside.
⅔ cup - all-purpose flour, ½ teaspoon - salt
In a 8x8 square baking pan lined with parchment paper, pour in the brownie mixture and leave a little bit to the side. Smooth that out.
Pour over the cream cheese mixture and smooth it out. Put a few dollops of the leftover brownie mixture and swirl the mixture with a knife or an offset spatula to create pretty swirls.
Bake for 30-33 minutes or until the a toothpick inserted comes out with a few crumbs.
Let it cool and then refrigerate for at least 2 hours for best results
Cut into 9 squares and enjoy!